The part of a person's hairstyle which covers the forehead.
1734, The Koran: Commonly Called the Alkoran of Mohammed, translated by George Sale, Sura 96, Congealed Blood, http://www.gutenberg.org/cache/epub/7440/pg7440-images.html
Doth he not know that GOD seeth? / Assuredly. Verily, if he forbear not, we will drag him by the forelock, / the lying, sinful forelock. / And let him call his council to assistance: / we also will call the infernal guards to cast him into hell.
The part of a horse's (or similar animal's) mane that lies on its forehead.
noun
A wedge pushed through a hole at the end of a bolt to hold it in place.